It's probably because the site is lagging a bit due to a lot of people trying to access ck. It's why that auth thing is currently active when you try...
When i did that (i used to run 10+ accounts daily for over 4 years), i used to buy proxies so the account would have the same ip everytime and avoid...
i have a pricer script but it goes item by item and usually takes ages to update, so i use it but for nerks and codestones only, because it would be...